If it actually biodegrades and is converted to gas, then the litter would disappear, and that's desirable.

如果垃圾真的能被生物降解并转化为气体，那垃圾就会消失，所以是可取的。

Unfortunately, it only biodegrades under certain conditions.

不幸的是，它仅在某些条件下才会生物降解。

And then as it biodegrades, you're building up methane that methane is gonna be pumped out and put to beneficial use, usually as energy.

然后随着它生物降解，你会积累甲烷，甲烷将被会抽出并用于有益的用途，通常是用作能源。